2 * Copyright (C) 2007 Red Hat. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
20 #include <linux/string.h>
21 #include <linux/xattr.h>
22 #include <linux/posix_acl_xattr.h>
23 #include <linux/posix_acl.h>
24 #include <linux/sched.h>
25 #include <linux/slab.h>
28 #include "btrfs_inode.h"
31 #ifdef CONFIG_BTRFS_FS_POSIX_ACL
33 static struct posix_acl *btrfs_get_acl(struct inode *inode, int type)
38 struct posix_acl *acl;
40 if (!IS_POSIXACL(inode))
43 acl = get_cached_acl(inode, type);
44 if (acl != ACL_NOT_CACHED)
49 name = POSIX_ACL_XATTR_ACCESS;
51 case ACL_TYPE_DEFAULT:
52 name = POSIX_ACL_XATTR_DEFAULT;
58 size = __btrfs_getxattr(inode, name, "", 0);
60 value = kzalloc(size, GFP_NOFS);
62 return ERR_PTR(-ENOMEM);
63 size = __btrfs_getxattr(inode, name, value, size);
65 acl = posix_acl_from_xattr(value, size);
70 set_cached_acl(inode, type, acl);
73 } else if (size == -ENOENT || size == -ENODATA || size == 0) {
74 /* FIXME, who returns -ENOENT? I think nobody */
76 set_cached_acl(inode, type, acl);
84 static int btrfs_xattr_acl_get(struct dentry *dentry, const char *name,
85 void *value, size_t size, int type)
87 struct posix_acl *acl;
90 if (!IS_POSIXACL(dentry->d_inode))
93 acl = btrfs_get_acl(dentry->d_inode, type);
99 ret = posix_acl_to_xattr(acl, value, size);
100 posix_acl_release(acl);
106 * Needs to be called with fs_mutex held
108 static int btrfs_set_acl(struct btrfs_trans_handle *trans,
109 struct inode *inode, struct posix_acl *acl, int type)
117 ret = posix_acl_valid(acl);
124 case ACL_TYPE_ACCESS:
125 mode = inode->i_mode;
126 name = POSIX_ACL_XATTR_ACCESS;
128 ret = posix_acl_equiv_mode(acl, &mode);
131 inode->i_mode = mode;
135 case ACL_TYPE_DEFAULT:
136 if (!S_ISDIR(inode->i_mode))
137 return acl ? -EINVAL : 0;
138 name = POSIX_ACL_XATTR_DEFAULT;
145 size = posix_acl_xattr_size(acl->a_count);
146 value = kmalloc(size, GFP_NOFS);
152 ret = posix_acl_to_xattr(acl, value, size);
157 ret = __btrfs_setxattr(trans, inode, name, value, size, 0);
162 set_cached_acl(inode, type, acl);
167 static int btrfs_xattr_acl_set(struct dentry *dentry, const char *name,
168 const void *value, size_t size, int flags, int type)
171 struct posix_acl *acl = NULL;
173 if (!inode_owner_or_capable(dentry->d_inode))
176 if (!IS_POSIXACL(dentry->d_inode))
180 acl = posix_acl_from_xattr(value, size);
185 ret = posix_acl_valid(acl);
191 ret = btrfs_set_acl(NULL, dentry->d_inode, acl, type);
193 posix_acl_release(acl);
198 int btrfs_check_acl(struct inode *inode, int mask, unsigned int flags)
202 if (flags & IPERM_FLAG_RCU) {
203 if (!negative_cached_acl(inode, ACL_TYPE_ACCESS))
207 struct posix_acl *acl;
208 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
212 error = posix_acl_permission(inode, acl, mask);
213 posix_acl_release(acl);
221 * btrfs_init_acl is already generally called under fs_mutex, so the locking
222 * stuff has been fixed to work with that. If the locking stuff changes, we
223 * need to re-evaluate the acl locking stuff.
225 int btrfs_init_acl(struct btrfs_trans_handle *trans,
226 struct inode *inode, struct inode *dir)
228 struct posix_acl *acl = NULL;
231 /* this happens with subvols */
235 if (!S_ISLNK(inode->i_mode)) {
236 if (IS_POSIXACL(dir)) {
237 acl = btrfs_get_acl(dir, ACL_TYPE_DEFAULT);
243 inode->i_mode &= ~current_umask();
246 if (IS_POSIXACL(dir) && acl) {
247 struct posix_acl *clone;
250 if (S_ISDIR(inode->i_mode)) {
251 ret = btrfs_set_acl(trans, inode, acl,
256 clone = posix_acl_clone(acl, GFP_NOFS);
261 mode = inode->i_mode;
262 ret = posix_acl_create_masq(clone, &mode);
264 inode->i_mode = mode;
267 ret = btrfs_set_acl(trans, inode, clone,
271 posix_acl_release(clone);
274 posix_acl_release(acl);
279 int btrfs_acl_chmod(struct inode *inode)
281 struct posix_acl *acl, *clone;
284 if (S_ISLNK(inode->i_mode))
287 if (!IS_POSIXACL(inode))
290 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
291 if (IS_ERR_OR_NULL(acl))
294 clone = posix_acl_clone(acl, GFP_KERNEL);
295 posix_acl_release(acl);
299 ret = posix_acl_chmod_masq(clone, inode->i_mode);
301 ret = btrfs_set_acl(NULL, inode, clone, ACL_TYPE_ACCESS);
303 posix_acl_release(clone);
308 const struct xattr_handler btrfs_xattr_acl_default_handler = {
309 .prefix = POSIX_ACL_XATTR_DEFAULT,
310 .flags = ACL_TYPE_DEFAULT,
311 .get = btrfs_xattr_acl_get,
312 .set = btrfs_xattr_acl_set,
315 const struct xattr_handler btrfs_xattr_acl_access_handler = {
316 .prefix = POSIX_ACL_XATTR_ACCESS,
317 .flags = ACL_TYPE_ACCESS,
318 .get = btrfs_xattr_acl_get,
319 .set = btrfs_xattr_acl_set,
322 #else /* CONFIG_BTRFS_FS_POSIX_ACL */
324 int btrfs_acl_chmod(struct inode *inode)
329 int btrfs_init_acl(struct btrfs_trans_handle *trans,
330 struct inode *inode, struct inode *dir)
335 #endif /* CONFIG_BTRFS_FS_POSIX_ACL */